This invention relates to an improved and simplified window frame construction that is less expensive to manufacture and allows for the use of optional accessories. A window assembly also includes a highly efficient energy filter system.
The Rolscreen Company, Pella, Iowa, has marketed a window assembly as represented in FIGS. 19-21 which includes a fixed glazing panel 10 and a removable panel 12. Pivot retention clips 14 are carried on removable panel 12 and are received in notches 16 to hold the panel in place. A breather passageway 18 allows ambient outside air to communicate with the space between the glazing panels 10 and 12. The construction of this window requires separate manufacturing steps to form the breather passageway 18 and the notch 16 in the rail frame member 20 and the stile frame member 22. One of the objects of this invention is to simplify this manufacturing procedure so that frame components can be in part mass produced and customized as required with a minimum of manufacturing steps.
The Rolscreen Company has made popular a window assembly having an adjustable blind positioned between the removable inside glazing panel and the outside fixed window unit. While this product has been very successful, it is desirable to have a variety of accessory options if they can be provided at a reasonable cost to manufacture. An objective of this invention thus is to provide a basic window frame construction which allows for final modification at the time of assembly for construction of any number of different accessorized window assemblies which may include multiple accessories between the glazing panels.
In the area of heat and light energy control systems, substantial work has been done in recent years representative of which is disclosed in the Southwall Technologies, Inc., Palo Alto, Calif., Meyer, et al. U.S. Pat. No. 4,799,745, Jan. 24, 1989. While the basic energy transmission control systems are known, improvements are needed in the combining these various systems to give the most affective and efficient system for different environmental conditions. Thus an object of this invention is to uniquely combine certain features of different systems into one to maximize their benefits to the window consumer. It is an object to filter out the ultraviolet light that causes fading while maximizing the transmission of visible light and then again filtering out the near infrared and long wave light. Ultraviolet rays are from 0 to 390 nanometers while the visible region is 390 to 760 and near infrared is from 760 to 2,500. The long wave light is above 2,500. This invention has as an object to provide an energy control system that will filter out as much energy as possible at the top end of the ultraviolet region near its interface with the visible light. This would generally include wave length on the order of 360 to 380 nanometers. It is also an object to strike a balance between the objectives of minimizing near infrared transmission while maximizing visible light.